3.0Low
CVE-2026-87876
Two case-insensitive comparisons on request-derived usernames outside the main authorization path in CUPS's scheduler (printer ACL validation and private-attribute filtering) could allow bypass of username-based access controls in certain configurations.
What this means for your business
- An attacker can use it from inside the same network, with an ordinary user login, but only after tricking someone into an action such as opening a file or a link.
What to do
- 1Ask your IT team or provider whether any of your systems use the affected product.
- 2If you do, follow the vendor's guidance. No patch reference has been published yet.
Not sure if your company is exposed?
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Scoring
- CVSS
- 3.0 (v3.1)
- Vector
CVSS:3.1/AV:A/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N- Weakness
- CWE-178
- Assigned by
- secalert@redhat.com
Dates
- Published
- 2026-09-09
- Last modified
- 2026-09-10
- Sources
- NVD
References
- https://access.redhat.com/security/cve/CVE-2026-87876
- https://bugzilla.redhat.com/show_bug.cgi?id=2530991
- https://github.com/OpenPrinting/cups/commit/88e67c00c130a45f3a1edf36686f7a0b2982fef8
- https://github.com/OpenPrinting/cups/commit/f56844dbe4a54a9f8e1aeb3b913fbee614156bdb
- https://github.com/OpenPrinting/cups/security/advisories/GHSA-r8jp-q6fh-g5r2
- https://github.com/OpenPrinting/cups/security/advisories/GHSA-r8jp-q6fh-g5r2